Cut each zucchini in half lengthwise; scoop out pulp, leaving a 1/4-inch-thick shell. Place zucchini halves, cut sides up, in a shallow roasting pan. Sprinkle with 1/2 teaspoon salt.
Preheat oven to 375°.
Cook potato in boiling water 2 minutes or until crisp-tender; drain.
Heat butter and oil in a nonstick skillet over medium-high heat until butter melts. Add onion, ginger, garlic, and chile, and sauté 3 minutes. Stir in flour and next 4 ingredients (flour through cumin). Cook over medium-low heat 5 minutes, stirring frequently. Stir in 3/4 teaspoon salt, potato, peas, and cilantro.
Pat zucchini dry with paper towels; spoon about 1/3 cup potato mixture into each zucchini half. Cover and bake at 375° for 20 minutes or until zucchini is tender.
Great spicy flavor; advance prep made for an easy dish to prepare. Used whole wheat flour; dash of red pepper flake in place of serrano pepper. Served with dizzle of yougurt. Will make again, good for company and family. Served with lamb chops and salad of cucumber, tomatoes & feta cheese.
Great! Subbed whole wheat flour as suggested. Replaced the peas with chopped tomato and mushroom, and used a small green bell pepper instead of the serrano, because I had lots of veggies from the garden to use up. Grilled directly over low-burning coals for about 30 min (along side bone-in chicken marinated in the sauce from Spicy Yogurt Marinated Chicken with Couscous, from this site). My zucchini were huge (about a foot long and as big around as my arm), so I used about a half recipe of the stuffing to fill one squash, which was plenty for two of us... I didn't reduce the spice amounts though, and might even use more next time. It was great! Even picky, anti-veggie boyfriend liked it. Next time I might top it with some herbed breadcrumbs and/or feta & fresh basil at the end of the grilling time. Very versatile recipe for using up fresh garden produce, and tasty & impressive-looking enough to serve to guests any time. Will make regularly. (And am looking forward to having leftovers to fold into an omelette the next day!)